Safety is a key issue for lithium-ion (Li-ion) battery applications. Conventional organic electrolytes have high vapor pressures, and are flammable. In contrast, molten salt electrolytes have high melting points and low vapor pressures, therefore they provide higher safety levels than organic electrolytes.
However, conventional cathode electroactive materials used in a Li-ion battery, such as LiCoO2 and LiNiO2 based cathodes (positive electrodes), have cost and thermal stability problems, even in a Li-ion battery with molten salt electrolyte. In order to further improve the performance of Li-ion batteries with a molten salt electrolyte, it is necessary to find other cathode materials with high thermal stability.